Abstract:
The installed capacity of electrostatic-fabric integrated precipitators (EFIPs), a new type of dust collector, in coal-fired power plants has exceeded 200 billion watts in China. However, there still lacks a better understanding of the removal performance on multiple pollutants of EFIPs. Therefore, the removal efficiencies for six kinds of pollutants in flue gas from the circulating fluidized bed boiler, including Hg, SO
3, dust, PM
1, PM
2.5 and PM
10 were tested in coal-fired power plants A and B, respectively. Mercury was tested by the 30B method of US EPA, SO
3 was tested by
Performance Test Code for Wetlimestonegypsum Flue Gas Desulphurization(DL/T 998-2006) for sampling and
Water Quality-Determination of Sulfate-barium Chromate Spectrophotometry(HJ/T 342-2007) for analysis, dust was tested by
Determination of Particulates and Sampling Methods of Gaseous Pollutants Emitted from Exhaust Gas of Stationary Source (GB/T 16157-1996), and fine particles were tested by
Stationary Source Emissions-Determination of PM
10/PM
2.5 Mass Concentration in Flue Gas-Measurement at Low Concentrations by Use of Impactors (ISO 23210-2009) to ensure the reliability of the data. The results showed that the particulate matter collection efficiency of dust, PM
10 and other particulate pollutants by EFIP were higher than 99%. Meanwhile, the mass balance of mercury across the EFIP of power plants A and B was 112.05% and 72.78%, respectively, within the acceptable ranges. The proportion of particulate-bound mercury in the flue gas at the inlet of EFIP in power plant B was as high as 97%, the collection efficiency of the particulate-bound mercury by EFIP was 99.93%, and the efficiency of gaseous mercury was 86.84%. The dust layer attached on the surface of the filter bag showed a certain adsorption to mercury, and SO
3 as well. The removal efficiencies of SO
3 by EFIP in power plants A and B were 90.04% and 61.73%, respectively. The removal efficiencies were also influenced by the composition of fly ash and the adsorption capacity of fly ash.